This site may earn affiliate commissions from the links on this page. Terms of use.

A quirk of physics has allowed astronomers to spot a distant exoplanet about 25,000 light years away in a densely packed region of the galaxy known as the galactic bulge. This is notable not only due to its location, but because of the nature of the planet itself. It appears to be in the habitable zone of its star — a zone that could support the presence of liquid water.

The planet was spotted using an effect called “microlensing.” This occurs when one star passes in front of another from our perspective. The gravity of the closer star bends the light from the more distant one like a lens, which gives astronomers a chance to better evaluate the lightcurve from the distant star to learn about its properties. In this case, the microlensing event MOA-2011-BLG-293Lb was detected by all the projects that watch for microlensing.

With careful analysis, astronomers determined that the exoplanet was orbiting 1.1AU from its star, which is slightly smaller and colder than the sun. It might be a little chilly, but liquid water is possible. 1AU is the distance from Earth to the sun, so this system looks a bit like ours except for one key difference — the planet is a gas giant four times the size of Jupiter. Life as we know it cannot exist on such a world, but there are likely moons orbiting this behemoth that could be quite temperate. They may even be warmer than expected due to tidal forces from the large gas giant nearby.

At 25,000 light years distance we’ll probably never get a chance to check out this potentially habitable system, but this discovery shows how precise our planet detecting technology is becoming. That list of exoplanets is getting quite long — maybe one day we’ll hit the jackpot and someone will be looking back at us.